Field
The present disclosure relates to the emergency (and planned) shutdown of a boiling water nuclear reactor (BWR) via the insertion of negative reactivity into the core.
Description of Related Art
In response to a scram signal during the operation of a boiling water nuclear reactor (BWR), a hydraulic control unit shuts down the reactor by inserting neutron-absorbing control rods into the core. In a conventional hydraulic control unit, a control rod is driven into the core by pressurized water that is applied to a metal piston and includes a seal formed by an elastomeric O-ring. However, the conventional piston/O-ring approach may be prone to leaks. As a result, regular maintenance (e.g., changing the elastomeric O-ring) must be performed to ensure proper functionality during a scram operation.